The effect of powder aerosol compared to pressurized aerosol.

A comparison was performed between inhalation of salbutamol as a powder aerosol or as a pressurized aerosol. Seven intrinsic asthmatics, well-trained in inhalation technique, were studied in an open randomized crossover comparison of the two different modes of administration. Five doses were inhaled of salbutamol from the pressurized aerosol, 0.1-2.4 mg, and five doses as a powder aerosol from a Rotahaler, 0.2-4.8 mg. The FEV1 dose-response curves were almost identical indicating bronchodilating equipotency between the two modes of administration. A preliminary report is given of the effects on morning cortisol of inhalation of beclomethasone dipropionate as a powder aerosol or as a pressurized aerosol in 10 healthy volunteers trained in inhalation technique. Morning cortisol decreased to the same degree after both modes of administration and the decrease was dose-dependent when beclomethasone dipropionate was given in the doses 200 micrograms, 500 micrograms and 1000 micrograms q.i.d. Thus, in patients with a good inhalation technique the powder aerosol does not seem to be better than the pressurized aerosol. We think, however, that it could be offered as an alternative to patients with poor inhalation technique.